<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="https://cdn.staticfile.org/react/16.4.0/umd/react.development.js"></script>
    <script src="https://cdn.staticfile.org/react-dom/16.4.0/umd/react-dom.development.js"></script>
    <script src="https://cdn.staticfile.org/babel-standalone/6.26.0/babel.min.js"></script>
</head>
<body>
    <!-- 语法：jsx 
        是将html放在一个组件中
    -->
    <div id="app"></div>
    <script type="text/babel">
        class Hello extends React.Component{
            constructor(props){
                super(props);
                this.state={
                    msg:"hello world"
                    arr:[1,2,3]
                }
            }
            render(){
                // 1.列表渲染
                // 2.事件
                
                return (
                    <div>
                    {this.state.arr.map((item,index)=>{
                        return (<p key={index}>{item}</p>)
                    })}
                    
                        <div onClick={this.handleClick}>{this.state.msg}</div>
                    </div>
                    )

            }
            handleClick=()=>{
                this.setState({
                    msg:"change"
                })
            }
        }
        ReactDOM.render(
            <Hellow/>,
            document.getElementById("app")     
               )
    
    </script>
</body>
</html>